Both my wife and I work full time jobs and are managing and doing much of the work on a flip currently. On the one hand, it's not ideal and it wasn't our original plan, but on the other hand, you can't beat the first hand knowledge and experience. I have a construction background so I think it's pretty feasible relative to my skill level, but if you haven't worked in construction or done a lot of DIY work, it's probably not recommended. Definitely identify a contractor who can help you out. If you're asking one to serve as your General Contractor and schedule and oversee subs, you can expect to pay more. If you are willing to work as the GC and handle all the scheduling and work of the subs, you won't be paying the GC overhead so you'll save a little (but could cost yourself more in the long run if you don't know what you're doing.) If it's your first and you're not experienced at swinging a hammer, it's probably worthwhile to hire a GC. You'll save money in the long run.
As for working with a Realtor, be cautious. Find one who is used to working with investors because it's very different than working with buyers who are buying retail. He/she needs to understand that you'll look at 50 properties, offer on 10 and maybe land 1. That's a lot of time and legwork for your Realtor and not all of them are willing. Also, if you're in a really competitive market, you need a Realtor who can set up alerts off the MLS for properties that meet your criteria and one who is available right away to show you properties ASAP or you'll get beat out by other investors. Rapid response from your Realtor is essential. Once you get a feel for looking at properties and estimating costs, you might even be able to submit offers sight unseen, which will save you both time. IF you get into contract, you'll have the inspection period to run your numbers again and you can back out if you need to. Then be kind to your Realtor. If you DO land one, make sure he/she gets the listing when it's time to sell. It's only right.
Don't shy away from acting because you have a FT job. Most people can't make the leap into FT investing right away and that W2 income will really help you get financing. Just dedicate yourself to getting up early and staying up late to "work" your RE business and it will happen for you!